word of healing doesnt work?

im a m/w and my elite is word of healing... in pvp i use word of healing on people and it only heals for +67 +67(from divine boon) when their hp is 40% to 50%. It only heals like +150 +67 when my target's hp is around 20% !!! hes almost about to die!!! whats wrong? i thought it was supposed to heal more when your ally is under 50% not 10% to 20%

The bonus heal is applied after all other heals. If they're at 40%, you cast word of healing and they're then at 46%, then it applies your divine favor bonus and he's up over 50%. At that point it won't apply the word of healing <50% bonus.

Thanks! I'd been wondering about that as well. Makes good sense.